The present invention relates to an apparatus for uniformly dispersing a microwave and a heating system employing the apparatus. More particularly, the present invention relates to an apparatus for uniformly dispersing a microwave which can uniformly disperse a microwave having a predetermined frequency outputted from a microwave generating means, and a heating system employing the apparatus for uniformly dispersing a microwave wherein a heating chamber of the heating system is defined by the apparatus and a uniform electric field is formed by uniformly dispersing the microwave in the heating chamber so as to evenly heat and dry an object to be heated that is contained in the heating chamber.
Generally, in a heating system such as a microwave oven for heating foodstuffs by using a microwave having a predetermined frequency or a microwave drying apparatus for drying wood, sludge, wastes, grain, rubber and the like, a microwave of 2.45 GHz or 915 MHz is generated by a microwave generating means using an oscillator such as a magnetron, and the generated microwave is guided to the interior of the heating chamber and heats and dries an object to be heated that is put in the heating chamber.
The microwave has a predetermined wavelength. For example, assuming that the frequency of the microwave is 2.45 GHz, the wavelength of the microwave is given as the following equation (1):
xcexg=c/f=(3xc3x97108 m/sec)/(2.45xc3x97109 Hz)≈12 cmxe2x80x83xe2x80x83(1) 
where xcexg is a wavelength of the microwave, c is the speed of light of 3xc3x97108 m/sec, and f is a frequency of the microwave.
In the heating system for heating and drying an object to be heated by using the microwave, all of the inner wall surfaces and the top and bottom surfaces of the heating chamber are usually planar.
Therefore, when the microwave outputted from the microwave generating means is guided into the heating chamber, the microwave is incident onto a planar surface 10, such as the inner wall surfaces and the top and bottom surfaces of the heating chamber, and then reflected by the planar surface 10 as shown in FIG. 1, so that the microwave is not uniformly dispersed but defectively reflected.
As the microwave is defectively reflected, the microwave is not uniformly distributed in the heating chamber. Thus, an object to be heated that is contained in the heating chamber is not evenly heated as a whole, so that the object is heated with the maximally and minimally heated points produced therein. That is, since the object is heated in such a manner that the maximally and minimally heated points are alternately produced therein at an interval of the wavelength of the microwave, the object is excessively heated at the maximally heated point, whereas it is not sufficiently heated at the minimally heated point. Thus, non-uniform heating of the object is produced.
In order to solve the above problems, a conventional heating system has a radio wave stirrer, such as a dispersion fan, mounted on the top of the heating chamber and causes the radio wave stirrer to be rotated so as to uniformly disperse the microwave and/or causes the object to be rotated, thereby evenly heating the object.
However, the rotation of either the radio wave stirrer or the object to be heated requires an additional driving motor for producing rotational force, a power transmitting mechanism for transmitting the rotational force from the driving motor, etc. This results in some problems including a complicated structure, increased production costs, higher consumption of electric power and the like.
An object of the present invention is to provide an apparatus for uniformly dispersing a microwave, which can uniformly disperse the microwave having a predetermined frequency.
Another object of the present invention is to provide a heating system employing the apparatus for uniformly dispersing the microwave, wherein the apparatus defines a heating chamber and uniformly disperses the microwave so as to evenly heat an object to be heated that is contained in the heating chamber.
In order to accomplish the above objects, an apparatus for uniformly dispersing the microwave according to the present invention comprises a body including a plurality of reflective portions which are made of materials capable of reflecting the microwave and have the horizontal top surfaces and vertical side surfaces. The width of the plurality of reflective portions can be set as 1/n (n=1, 2, 3, . . . ) times as large as a wavelength xcexg of the microwave. More preferably, the width is set as 1/4n (for example, xcexg/4, xcexg/8, xcexg/12, . . . ) times as large as the wavelength xcexg of the microwave.
Further, the depth of each of the plurality of reflective portions may be set as a value obtained by multiplying the remainder, which is obtained by dividing the power of a natural number for the least primitive root of a prime number by the prime number, by the width of the reflective portion under the condition that a datum plane is defined by a height from the bottom surface corresponding to a value obtained by multiplying the width of the reflective portion by (prime numberxe2x88x921). Alternatively, the depth of each reflective portion may be set as a value obtained by multiplying the remainder, which is obtained by dividing a square of a natural number by a prime number, by the width W of the reflective portion under the condition that the datum plane is defined by the bottom surface.
Moreover, in the heating system according to the present invention, the top, bottom and inner wall surfaces of the heating chamber are formed by continuously and repeatedly coupling the aforementioned bodies. The body is also additionally installed on an inner surface of a door of the heating system. The microwave generated from the microwave generating means and guided into the heating chamber is uniformly dispersed in the heating chamber by the bodies to form a uniform electric field of the microwave, thereby evenly heating and drying the object to be heated.